1. Field of the Invention
The present invention relates to a micro-flow controlling pump to be used for controlling a micro-flow of a liquid in an experiment using a chemical agent for examining permeability of a membrane, reaction of a flow system, reflux of vital tissues, or the like.
2. Description of the Prior Art
Generally, an experiment for examining permeability of a flowing membrane, or the like necessitates it to control a micro-flow of a liquid.
For purpose of controlling the micro-flow, what is called an ironing pump or peristaltic pump has conventionally been utilized. According to this peristaltic pump, an elastic tube body made of silicon rubber or the like is subject to an compressing process using a roller, etc.; and a liquid is fed through this elastic tube body. Such an ironing pump has been disclosed in Japanese TOKKYO KOKAI No. 58-101282 for example.
However, such a conventional peristaltic pump has a problem that the liquid inevitably pulses through the tube body, influence of which cannot be neglected for controlling the micro-flow. To overcome the problem, it has been proposed to improve the compressing process using the roller and reduce the degree of pulsation of the liquid. However, this makes the resulting pump complicated in structure and inevitably leads to a high manufacturing cost.
Moreover, in a case of feeding a chemical liquid which is made by diluting a chemical agent to a low concentration, there arises another problem that the chemical liquid may be absorbed by the elastic tube body through the feed, and the thus absorbed chemical liquid may be dissolved again in another chemical liquid, thereby making it impossible to accurately watch behavior of the chemical agent, or the like.